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Every row

Showing 37 of 382 rows. One row per study per exposure: a study that tested two different things appears twice, once for each.

Scroll the table sideways to see every column.

Research and outcomes, 37 rows. Every row links to its source.
Exposure Question Direction Outcome measured Design People Effect size, as the source reported it Source
Alcohol Alcohol, tobacco and cannabis Prevention Mixed
why

Sustained mild and moderate drinking carried lower risk than not drinking, sustained heavy drinking higher risk, and cutting down from heavy to moderate lower risk. Observational, with the same abstainer problem.

Incident all-cause dementia over a mean 6.3 years cohort study 3,933,382 Sustained heavy drinking aHR 1.08 (95% CI 1.03-1.12); heavy-to-moderate reduction aHR 0.92 (0.86-0.99) JAMA Network Open 2023
✓ Peer-reviewed PMID 36745453
Alcohol Alcohol, tobacco and cannabis Prevention Mixed
why

U-shaped: long-term abstainers had 47% higher risk than moderate drinkers, and above 14 units a week each extra 7 units raised risk by 17%. Neither end of the range looks like a benefit of drinking.

Incident dementia over 23 years cohort study 9,087 Abstinence in midlife vs 1-14 units/week: hazard ratio 1.47 (95% CI 1.15 to 1.89). Among those drinking >14 units/week, "a 7 unit increase in alcohol consumption was associated with a 17% (95% confidence interval 4% to 32%) increase in risk of dementia". CAGE score >2: HR 2.19 (1.29 to 3.71); alcohol-related hospital admission: 4.28 (2.72 to 6.73) BMJ 2018
✓ Peer-reviewed PMID 30068508
Birth cohort and calendar period (secular trend in dementia) All modifiable factors together Prevention Mixed
why

The two measures moved in opposite directions over 2015-2021: standardised incidence fell from 3.5% to 2.8% per year while prevalence rose from 10.5% to 11.8%; gaps between Black or Hispanic and White beneficiaries narrowed.

Age- and sex-standardised incidence and prevalence of diagnosed dementia among US Medicare fee-for-service beneficiaries, 2015-2021 cohort study not stated The overall age and sex standardized incidence decreased between 2015 and 2021 from 3.5% to 2.8%. Prevalence increased during this time from 10.5% to 11.8% BMJ 2025
✓ Peer-reviewed PMID 40393738
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Treatment Mixed
why

The review's own summary points two ways: CSF biomarker tests were mostly cost-effective against cognitive assessment or imaging, while blood biomarker tests showed mixed results; every included study was model-based.

Cost-effectiveness of CSF and blood biomarker testing for AD diagnosis across nine model-based economic evaluations systematic review not stated not established — systematic review without meta-analysis; the abstract reports no pooled estimate. European Journal of Health Economics 2026
✓ Peer-reviewed PMID 41385058
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Treatment Mixed
why

The findings point two ways: the p-tau217/Aβ42 ratio tracked AD-related factors (MCI, AD dementia, future progression, age, APOE ε4) more closely than either marker alone and had few intermediate results, but it was also related to kidney function, diabetes and hearing loss, and medical morbidities were most frequent among intermediate classifications.

Associations of plasma p-tau217, Aβ42/40 and p-tau217/Aβ42 with AD-related factors and with medical comorbidities (kidney function, diabetes, hearing loss) in a health-system biobank cross-sectional study 617 not established — pubmed abstract reports no numeric effect size. Annals of neurology 2026
✓ Peer-reviewed PMID 41447112
Blood biomarker test (p-tau217 / amyloid ratio) Care, carers and services Treatment Mixed
why

Direction is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Performance varied widely across tests, from 49.3% to 91.4% pooled sensitivity and 61.5% to 96.7% pooled specificity at a single cut-point, with most studies at high risk of bias.

Pooled sensitivity and specificity of 31 blood-based biomarker tests for Alzheimer pathology in cognitively impaired people meta-analysis not stated the pooled sensitivity ranged from 49.3% (95% confidence interval [CI]: 41.2-57.4) to 91.4% (95% CI: 86.6-94.6), and the pooled specificity ranged from 61.5% (95% CI: 45.6-75.3) to 96.7% (95% CI: 87.8-99.2) Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 41193403
Blood biomarkers (GFAP, NfL, p-tau181) for staging and prognosis Care, carers and services Treatment Mixed
why

The results point different ways: diagnostic confidence rose 1.43 points, but diagnosis changed in only 17.2% and management in 27.7%, below the 30% threshold the investigators set as clinically significant; a non-elevated result reduced amyloid PET use, and patients with elevated results had higher anxiety at 2-3 months.

Change in clinician diagnostic confidence, diagnosis and management after plasma p-tau181 testing in a memory clinic, and patient wellbeing (SUITABLE) cohort study 100 Clinician diagnostic confidence averaged 1.43 points higher after p-tau181 testing (95% confidence interval [CI] 1.02 to 1.84, p < 0.0001). After testing, 27.7% (95% CI 18.9% to 36.4%, p = 0.31) of patients had a change in management and 17.2% of patients had a change in diagnosis - significantly lower than the 30% threshold (95% CI 9.5% to 24.9%, p = 0.004) Alzheimer's & Dementia: Translational Research & Clinical Interventions 2026
✓ Peer-reviewed PMID 42254757
Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services Prevention Mixed
why

The findings point different ways: lower eGFR raised every blood biomarker except Aβ42/40 (a test-interpretation caveat), yet impaired kidney function did not itself raise dementia risk (HR 0.93), while the association between high NfL and dementia was about twice as strong in people with impaired kidneys.

Blood AD biomarker levels by kidney function (eGFR), and incident dementia over a mean 8.3 years by kidney function and NfL cohort study 2,279 At eGFR = 30 mL/min/1.73 m2, estimated differences were as follows: p-tau181: β, 0.22 [95% CI 0.09-0.35]; p-tau217: β, 0.20 [95% CI 0.10-0.31]; t-tau: β, 0.24 [95% CI 0.05-0.42]; NfL: β, 0.88 [95% CI 0.80-0.95]; GFAP: β, 0.10 [95% CI 0.03-0.16] ... impaired kidney function (eGFR < 60 mL/min/1.73 m2) was not associated with an increased hazard of dementia compared with preserved kidney function (eGFR ≥ 60 mL/min/1.73 m2) (hazard ratio [HR], 0.93 [95% CI 0.72-1.21]). The relationship between increased (high vs low) NfL and dementia was stronger among individuals with impaired (vs preserved) kidney function (HR, 3.85 [95% CI 1.87-7.95] vs HR, 1.84 [95% CI 1.34-2.53], respectively) Neurology 2026
✓ Peer-reviewed PMID 41337685
Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services Prevention Mixed
why

The two measures behaved differently: baseline plasma p-tau217 predicted later cognitive decline about as well as entorhinal tau PET (ρ -0.47 vs -0.55), but over time p-tau217 rose then decelerated and tracked concurrent cognitive change only weakly (ρ -0.24) or not at all in the PET substudy, whereas regional tau PET change correlated strongly with concurrent decline.

Prognostic association with, and concurrent tracking of, cognitive change in preclinical AD: plasma p-tau217 versus tau PET cohort study 1,707 Baseline associations with longitudinal change in PACC score in Aβ+ participants were strongest in the entorhinal cortex (correlation [ρ] = -0.55; 95% CI, -0.63 to -0.45) and plasma p-tau217 levels (ρ = -0.47; 95% CI, -0.56 to -0.37) ... Levels of plasma p-tau217 increased significantly in Aβ+ participants before showing significant deceleration (χ2 = 21.7; P < .001) and were not associated with concurrent cognitive change in the tau PET substudy (ρ = -0.03; 95% CI, -0.23 to 0.16) but were modestly associated with concurrent cognitive changes in the full plasma sample (n = 1119; ρ = -0.24; 95% CI, -0.34 to -0.14) JAMA Neurology 2025
✓ Peer-reviewed PMID 40853684
Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services Treatment Mixed
why

The three markers pointed different ways: plasma p-tau217 distinguished amyloid/tau stages, GFAP tracked amyloid-driven tau progression, and NfL was only weakly linked to Alzheimer pathology and, in the authors' words, inadequate as a neuronal injury biomarker for AD.

Discrimination of amyloid/tau stages, tau progression, hippocampal atrophy and cognitive decline cohort study 1,275 not established — pubmed abstract results reports no numeric estimate. the library had recorded "p-tau217 auc 0.959", which does not appear in the abstract and is not… Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 41376134
Blood biomarkers (GFAP, NfL, p-tau217) for staging and prognosis Care, carers and services Treatment Mixed
why

The result points two ways: p-tau181 gave the best AUC for separating AD from controls, frontotemporal dementia and amyloid-negative Lewy body dementia, but that discrimination could not be reproduced when pre-defined cut-offs were applied, so cohort-specific cut-offs were needed.

Discrimination of AD from controls, frontotemporal dementia and Lewy body dementia by plasma Aβ42/40, p-tau181, GFAP and NfL, and transfer of predefined cut-offs to validation cohorts cross-sectional study 1,298 not established — pubmed abstract results prints no auc or other figure; it states only that p-tau181 showed the best area under the curve and that pre-defined… Alzheimer's & Dementia 2025
✓ Peer-reviewed PMID 40551285
CSF alpha-synuclein seed amplification assay Care, carers and services Treatment Mixed
why

Direction is for the test's accuracy against the reference standard; an accuracy result, not a health outcome. Results ranged from 55% to 100% sensitivity and 60% to 100% specificity across four laboratories using different protocols, with only fair agreement between them (kappa 0.246).

Sensitivity, specificity and cross-laboratory agreement for dementia with Lewy bodies cross-sectional study 30 On average, the 4 laboratories achieved 78.8% sensitivity (minimum 55%, maximum 100%), 77.5% specificity (minimum 60%, maximum 100%), and 78.5% accuracy (minimum 57%, maximum 100%) for discriminating DLB from controls ... A fair agreement of SAA results was obtained across the 4 laboratories (average κ = 0.246) Neurology 2026
✓ Peer-reviewed PMID 41604609
Carer psychosocial / skills intervention Care, carers and services Treatment Mixed
why

Peer support reduced distress to behavioural symptoms and increased social support and quality of life immediately after the intervention, but had no effect on depression/anxiety, loneliness, burden or competence, and no outcome was sustained at follow-up.

Caregiver distress, social support, health-related quality of life, depression/anxiety, loneliness, burden and competence after peer support meta-analysis 1,680 Peer support interventions significantly reduced caregiver distress to behavioral symptoms (standardized mean difference [SMD], -0.28; 95% confidence interval [CI], -0.55 to -0.02; p = 0.03), increased social support (SMD, 0.37; 95% CI, 0.06 to 0.67; p = 0.02), and HRQoL (SMD, 0.76; 95% CI, 0.07 to 1.46; p = 0.03) postintervention. However, no significant effects were observed on depression/anxiety, loneliness, caregiving burden, and caregiving competence/knowledge postintervention. None of the outcomes showed sustained effects at follow up Archives of gerontology and geriatrics 2026
✓ Peer-reviewed PMID 41690252
Cost of dementia care Care, carers and services Prevention Mixed
why

The two comparisons point different ways: overall utilization and payments were similar between amyloid-positive (A4) and amyloid-negative (LEARN) participants, but among A4 participants claims indicators of progression carried 45-103% higher payments.

Healthcare utilization and Medicare payments in cognitively unimpaired amyloid-positive versus amyloid-negative people, and by claims indicators of AD progression cohort study 367 45% payment increase for cognitive impairment (p=0.035) with a mean incremental cost of $140 per person per month (PPPM) (95% confidence interval [CI] $125-$155), 66% payment increase for AD (p=0.011) with a mean incremental cost of $207 PPPM (95% CI $188-$226), and 103% payment increase for high frailty (p<0.001) with a mean incremental cost of $303 PPPM (95% CI $283-$323) Journal of Prevention of Alzheimer's Disease 2026
✓ Peer-reviewed PMID 41926844
Cost-effectiveness of anti-amyloid antibody Care, carers and services Treatment Mixed
why

The review splits by drug class: at $100,000 per QALY every study found memantine cost-effective and more than half found the cholinesterase inhibitors so, whereas aducanumab, lecanemab and donanemab were not cost-effective in any study. A value result, not a clinical harm.

Cost-effectiveness of FDA-approved AD drugs across 23 published analyses (memantine, cholinesterase inhibitors, anti-amyloid antibodies) systematic review not stated At a willingness-to-pay (WTP) threshold of $100,000/QALY, all studies found memantine cost-effective, and more than half reported cost-effectiveness for donepezil, rivastigmine, and galantamine. Aducanumab, lecanemab, and donanemab were not cost-effective in any study. Under the WTP threshold of $150,000/QALY, value-based prices for aducanumab, lecanemab, and donanemab were estimated below $5,960, $15,700, and $33,700, respectively Journal of Alzheimer's Disease 2026
✓ Peer-reviewed PMID 41837605
Cost-effectiveness of multidomain prevention programme Care, carers and services Prevention Mixed
why

Direction is for value for money: APPLE-Tree had a 96% probability of being cost-effective per cognition point at a £30 000 threshold but only 12% on QALYs, which were slightly lower in the intervention arm. Post hoc subgroups suggested better value in non-White and socioeconomically disadvantaged participants.

QALYs over 24 months (primary) and cost per 1-point NTB cognition gain randomised trial 746 Mean adjusted QALYs were 1.511 (intervention) and 1.520 (control), an adjusted difference of -0.010 (95%CI -0.04 to -0.022). Mean adjusted (SD) costs were £2966 (3629) and £2551 (4439), respectively. Cost per 1-point NTB change z-score was £6809. At a £30 000 threshold, the probability of cost-effective was 12% and 96% based on QALYs and cognition, respectively Age and ageing 2026
✓ Peer-reviewed PMID 42328805
Dementia care management / navigation Care, carers and services Treatment Mixed
why

The two perspectives disagree: the digitally supported care management system dominated usual care for the public payer (lower costs, marginally more QALYs, 72-79% probability of cost-effectiveness) but cost €331,000 per QALY from a societal perspective (33-35% probability).

Caregiver QALYs, costs and incremental cost per QALY at six months, from public-payer and societal perspectives randomised trial 192 Caregivers in the intervention group gained QALYs (+0.004 [95% CI -0.003 to 0.012], P value = .225) and had lower costs from the public payer (-378€ [1926-1168], P value = .630), but higher costs from the societal perspective (+1324 [-3634 to 6284], P value = .599). The intervention dominated usual care from the payer perspective, whereas the incremental cost-effectiveness ratio was €331 000/QALY from a societal perspective Value in Health 2025
✓ Peer-reviewed PMID 39922302
Dementia screening / case finding Care, carers and services Treatment Mixed
why

MCI was diagnosed sooner (HR 1.21) but dementia diagnosis barely moved (HR 1.04, 95% CI 1.02-1.06). The outcome is detection, not health.

Timeliness of first MCI and dementia diagnosis cohort study 549,516 MCI diagnosis HR 1.21 (95% CI 1.16-1.27); dementia diagnosis HR 1.04 (95% CI 1.02-1.06) after an Annual Wellness Visit JAMA Network Open 2024
✓ Peer-reviewed PMID 39378037
Hospital admission after an emergency department visit Care, carers and services Treatment Mixed
why

Admission showed no evidence of an effect on 30-day mortality or subsequent inpatient days, but raised 30-day health care spending by $2547. An instrumental-variable estimate for marginal admissions.

30- and 90-day mortality, inpatient days and health care spending after hospital admission versus discharge cohort study 872,085 There was no evidence that hospital admission was associated with 30-day mortality rate (adjusted risk difference, -2.6 percentage points [pp] [95% CI, -5.2 to 0.1 pp]) or inpatient days (adjusted difference, 0.1 days [CI, -0.2 to 0.5 days]). Hospital admission was associated with higher 30-day health care spending (adjusted difference, $2547 [CI, $1390 to $3703]) Annals of internal medicine 2026
✓ Peer-reviewed PMID 42258826
Palliative / advance care planning Care, carers and services Treatment Mixed
why

Advance care planning strongly increased DNR documentation (OR 14.12) but did not change whether residents died in the nursing home (OR 1.62, 95% CI 0.72-3.66). Evidence on other end-of-life outcomes was limited and inconsistent, and no study came from a non-Western setting.

Do-not-resuscitate documentation; place of death meta-analysis not stated DNR documentation OR 14.12 (95% CI 3.95-50.47); nursing home death OR 1.62 (95% CI 0.72-3.66, not significant) Journal of the American Medical Directors Association 2026
✓ Peer-reviewed PMID 41198038
Ginkgo biloba Diet and supplements Treatment Mixed
why

In dementia there may be small-to-moderate benefits at six months (low-certainty evidence, I2 88-96%); in MCI ginkgo probably has little or no effect (moderate certainty); in subjective cognitive complaints the effect is very uncertain. Adverse events were similar to placebo.

Global clinical status, cognition and activities of daily living at 6 months in dementia and in MCI; adverse events meta-analysis 10,613 Dementia Thirteen studies (3288 participants) compared ginkgo with placebo for dementia. At six months, low-certainty evidence suggests that people taking ginkgo may have better global clinical status on a six-point Likert scale (lower is better; MD -0.06, 95% CI -1.00 to -0.20; I² = 88%; 5 studies, 1359 participants), better cognition measured by decreases on a short cognitive performance test (Syndrom-Kurztest; MD -1.86, 95% CI -3.48 to -0.24; I² = 96%; 9 studies, 2801 participants) ... Mild cognitive impairment ... moderate-certainty evidence suggests that ginkgo probably has little to no effect on global clinical status measured on the Clinical Dementia Rating Scale (MD -0.03, 95% CI -0.06 to 0.01; 3 studies, 631 participants; I² = 0%) The Cochrane database of systematic reviews 2026
✓ Peer-reviewed PMID 41641880
Omega-3 / fish and fish oil Diet and supplements Prevention Mixed
why

The biochemical primary outcome was met (DHA raised the CSF DHA-to-arachidonic-acid ratio versus placebo), but there was no difference in cognition or brain volume over 24 months. The authors recommend against further supplementation trials of this kind.

CSF DHA/AA ratio at 6 months (primary, target engagement); cognition and brain volumes at 24 months phase 2 trial 365 DHA supplementation increased CSF DHA/AA ratio at 6 months vs placebo (0.17 [95% CI 0.15-0.18] vs -0.02 [95% CI -0.04 to -0.0004]; difference 0.19 [95% CI 0.16-0.21]; p < 0.0001), independent of APOE ε4 status (interaction p = 0.71). Dropout was 38%, mainly due to COVID-19. No treatment differences were observed in brain volumes or cognitive performance over 24 months EBioMedicine 2026
✓ Peer-reviewed PMID 42315445
Air pollution Environment Prevention Mixed
why

The overall PM2.5 estimate includes no effect (HR 1.04, 95% CI 0.99-1.09). Only the studies that actively assessed everyone for dementia showed a clear effect (HR 1.42, 95% CI 1.00-2.02). Most studies were at high risk of bias.

Clinically diagnosed dementia meta-analysis not stated PM2.5 HR 1.04 per 2 ug/m3 (95% CI 0.99-1.09) overall; 1.42 (1.00-2.02) with active case ascertainment BMJ 2023
✓ Peer-reviewed PMID 37019461
Physical activity (general / dose) Exercise and activity Prevention Mixed
why

High overall and leisure-time activity were associated with lower dementia risk, but occupational and commuting activity were associated with higher risk. Certainty of evidence was very low to low.

All-cause dementia, Alzheimer's disease and vascular dementia by physical activity domain meta-analysis 4,227,297 high physical activity levels were associated with reduced risks of all-cause dementia (n=146 effect sizes; RR 0·80 [95% CI 0·75-0·86]; I2=97·4%), Alzheimer's disease (n=59; 0·79 [0·70-0·90]; I2=91·3%), and vascular dementia (n=21; 0·71 [0·58-0·87]; I2=77·5%); however, associations varied by domain. Leisure-time (k=20 studies; n=33 effect sizes; RR 0·76 [95% CI 0·65-0·88]; I2=96·6%) and household (k=1; 0·85 [0·74-0·98]) physical activity were associated with a reduced risk of all-cause dementia. By contrast, occupational (k=5; 1·20 [1·01-1·42]; I2=85·6%) and commuting (k=2; 1·10 [1·03-1·18]; I2=0·0%) physical activity were associated with an increased risk The Lancet. Public health 2026
✓ Peer-reviewed PMID 42612650
APOE genotype Genes (not modifiable) Prevention Mixed
why

Direction is for APOE genotype after 90: ε2 carriers had lower dementia risk, while the ε4 association was not statistically significant. Women and Black participants had higher risk than men and Asian participants. Age-standardised incidence was 116.82 per 1000 person-years.

Incident all-cause dementia after age 90 by APOE genotype, sex and race cohort study 805 The age-standardised incidence rate was 116·82 cases per 1000 person-years (95% CI 93·69-139·96). In Fine-Gray models, dementia risk was higher in female than in male participants (subdistribution hazard ratio [sHR] 1·89, 95% CI 1·30-2·76) and Black than Asian participants (sHR 1·75, 1·07-2·88), lower in APOE ε2 carriers than in non-carriers (sHR 0·39, 0·17-0·88), and not significantly higher in APOE ε4 carriers than in non-carriers (sHR 1·51, 0·92-2·47) The lancet. Healthy longevity 2026
✓ Peer-reviewed PMID 42551464
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Mixed
why

The intervention-control cognitive difference was statistically significant in the higher-genetic-risk halves and not in the lower halves, but neither genetic score significantly modified the intervention effect overall (P > 0.46); an exploratory sex difference emerged for the Alzheimer score.

Annual change in overall cognition (modified NTB) with a 2-year multidomain lifestyle intervention, by Alzheimer and coronary genetic risk score randomised trial 1,177 The intervention-control difference in annual overall cognition change (95% confidence interval) for participants with AD-GRS above/below the median (i.e. higher/lower risk) was 0.032 (0.002-0.063) versus 0.017 (-0.011 to 0.045), and for CAD-GRS above/below the median was 0.031 (0.002 to 0.059) versus 0.016 (-0.012 to 0.044). AD-GRS or CAD-GRS were not significantly related to the intervention effect overall (P > 0.46), but for AD-GRS there were differences between females and males (P = 0.024) Brain : a journal of neurology 2026
✓ Peer-reviewed PMID 40747850
Polygenic risk / GWAS loci Genes (not modifiable) Prevention Mixed
why

The study's own results point different ways: the polygenic score added to APOE for predicting AD/MCI and for progression from amyloid-positive MCI to AD, but amyloid deposition was predicted by APOE alone.

Prediction of AD, MCI, amyloid deposition and MCI-to-AD progression (AUC) by polygenic risk score with and without APOE case-control study 770 AD and MCI are predicted by both APOE genotype and PRS (area under the curve [AUC] = 0.82% and 68%, respectively). Amyloid deposition is predicted by APOE only (AUC = 79%). Further progression to AD of individuals with MCI and amyloid-positive status is predicted by PRS over and above APOE (AUC = 67%) Annals of Neurology 2019
✓ Peer-reviewed PMID 31199530
Rare copy-number variants (22q11.21 dosage, ABCA1 / ABCA7 deletions) Genes (not modifiable) Prevention Mixed
why

The two kinds of variant point opposite ways: deletions and loss-of-function alleles in ABCA1 and ABCA7 and 22q11.21 deletions raised AD risk, while 22q11.21 duplication lowered it (odds ratio 0.34 at exome-wide significance in replication). Not modifiable.

Alzheimer's disease case status (early- and late-onset) by rare copy-number variant burden and 22q11.21 dosage case-control study 22,319 ABCA1 (odds ratio [OR] = 5.77 [95% confidence interval 2.25; 17.06], p = 0.0002) and ABCA7 deletions contribute to this deletion burden (OR = 2.29 [1.44; 3.65], p = 0.0006), while CTSB LoF alleles appear as candidates (OR = 5.03 [1.50; 20.71], p = 0.0089) ... Replication in 33,977 affected individuals and 362,322 control subjects confirmed association for 22q11.21 dosage with exome-wide significance (ORSCARF2 = 0.34 [0.21; 0.53]; mega-p value = 5.52 × 10-7) American Journal of Human Genetics 2026
✓ Peer-reviewed PMID 42648288
Anti-amyloid antibody Medicines Treatment Mixed
why

A statistically detectable but very small cognitive effect (ADAS-Cog SMD -0.11) alongside 107 more cases of ARIA-E per 1,000. The reviewers' own conclusion is that removing amyloid does not seem to produce clinically meaningful effects — the sharpest disagreement in this table with how the individual trials were reported.

ADAS-Cog and CDR-SB at 18 months; ARIA meta-analysis 20,342 ADAS-Cog SMD -0.11 (95% CI -0.16 to -0.06); ARIA-E absolute risk difference +107 per 1,000 Cochrane Database of Systematic Reviews 2026
✓ Peer-reviewed PMID 41985900
Anti-amyloid antibody Medicines Treatment Mixed
why

CHMP refused the drug, then on re-examination recommended it only for people with one or no APOE4 copy, where the ARIA rates are lower. Benefit on cognition and harm from ARIA in the same document, with the restriction as the regulator's way of balancing them.

CDR-SB at 18 months and ARIA rates, in the APOE4-restricted group regulatory decision 1,521 "After 18 months of treatment, patients treated with Leqembi had a smaller increase in CDR-SB score than those who received placebo (1.22 versus 1.75)"; "8.9% of those with only one or no copy of ApoE4 experienced ARIA-E, compared with 12.6% of all patients ... 12.9% of patients in the restricted population experienced ARIA-H compared with 16.9% of the broader population"; placebo figures 1.3% and 6.8% European Medicines Agency 2024
⚠ Regulatory decision — not a study no DOI or PMID exists
Anti-amyloid antibody Medicines Treatment Mixed
why

Benefits were statistically present but every one fell below the minimum clinically important difference, against a number needed to harm of 9 for ARIA-oedema. Agrees with the Cochrane review and not with the trial reports.

Cognitive and functional scales against the MCID; ARIA meta-analysis 23,202 CDR-SB mean difference -0.18 (95% CI -0.34 to -0.03), below the MCID; ARIA-oedema NNH 9 Annals of Family Medicine 2024
✓ Peer-reviewed PMID 38253509
Anti-amyloid antibody Medicines Treatment Mixed
why

Approved on amyloid reduction (surrogate) while reporting higher ARIA rates than placebo; the notice reports no cognitive outcome.

Amyloid PET (surrogate marker); ARIA rates regulatory decision not stated not established — the library recorded "aria-e in 10% of lecanemab patients vs 1% placebo; aria-h in 6% vs 5%". investors.biogen.com timed out on repeated attempts… U.S. Food and Drug Administration (announced via Biogen press release) 2023
⚠ Regulatory decision — not a study no DOI or PMID exists
Anti-amyloid antibody Medicines Treatment Mixed
why

Two identically designed trials disagreed: EMERGE met its primary endpoint, ENGAGE did not.

CDR-SB at 78 weeks phase 3 trial 3,285 EMERGE: CDR-SB difference -0.39 vs. placebo (95% CI -0.69 to -0.09; P=.012); ENGAGE: CDR-SB difference +0.03 vs. placebo (95% CI -0.26 to 0.33; P=.833) Journal of Prevention of Alzheimer's Disease 2022
✓ Peer-reviewed PMID 35542991
Antihypertensives / BP lowering Medicines Prevention Mixed
why

Antihypertensive treatment improved cognitive scores by a small amount (SMD 0.06, moderate certainty) but the reduction in dementia incidence was not statistically significant (OR 0.89, low certainty). The drug-class rankings rest on one trial per class and are described as highly uncertain.

Cognitive function scores and incident dementia in hypertensive older adults (four RCTs) meta-analysis 16,823 Antihypertensive treatment significantly improved cognitive function scores (SMD, 0.06; 95% CI, 0.03-0.09; P < .001, GRADE moderate certainty) and showed a nonsignificant trend toward reduced dementia incidence (OR, 0.89; 95% CI, 0.76-1.05; P = .172, GRADE low certainty) Journal of the American Medical Directors Association 2026
✓ Peer-reviewed PMID 41962914
Antihypertensives / BP lowering Medicines Prevention Mixed
why

Antihypertensive use tracked lower Alzheimer's risk but not lower non-Alzheimer dementia risk, where treated and untreated hypertension looked the same. A single baseline blood pressure reading predicted neither.

Alzheimer's and non-Alzheimer dementia meta-analysis 31,250 Untreated vs treated hypertension: Alzheimer's dementia HR 1.42 (95% CI 1.08-1.87) Neurology 2024
✓ Peer-reviewed PMID 39141884
Metformin / antidiabetic Medicines Prevention Mixed
why

The split inside this one paper is the finding: the 41 observational studies show large benefits (SGLT2i OR 0.56, GLP-1RA OR 0.58) while the 23 randomised trials show no difference. When design and result disagree this cleanly, the trials are the ones to believe.

Incident dementia meta-analysis 3,462,926 Observational: SGLT2i OR 0.56 (95% CI 0.45-0.69), GLP-1RA OR 0.58 (0.46-0.73) vs non-users; RCTs: no difference Alzheimer's Research & Therapy 2024
✓ Peer-reviewed PMID 39716328
Sleep Sleep, mood and social life Prevention Mixed
why

Two findings point opposite ways: synchronised norepinephrine, blood-volume and CSF oscillations during natural NREM sleep were the strongest predictors of glymphatic clearance, while the sleep aid zolpidem suppressed those oscillations and glymphatic flow. Mouse work with no human outcome.

Glymphatic clearance during NREM sleep in mice, its drivers (norepinephrine and vasomotion oscillations) and its suppression by zolpidem None not stated not established — pubmed abstract reports no numeric effect size. Cell 2025
✓ Peer-reviewed PMID 39788123

How this table was built, and where it is weak →